mosquitto_rr protocol error

[howjmay]

platform
Ubuntu 16.04

I built rr_client on my local machine and once I ran it, I met protocol error.
error message: Error: A network protocol error occurred when communicating with the broker.
All of the other clients worked fine on my machine.
I used the following command mosquitto_rr -h <IP> -t <topic> -m <message> -e <response_topic>
Did I do something wrong with the command?

[ralight]

The problem is most likely because you are connecting to a broker that does not have MQTT v5 support. mosquitto_rr only works with MQTT v5.

[ralight]

I've changed things so the error message is clearer now. If you spot anything thing else like this that could do with better explanation please post another issue. Thanks for reporting this one!